On Fri, Oct 14, 2011 at 12:27:03PM +0800, Paul Wise wrote:
> On Fri, Oct 14, 2011 at 1:38 AM, Wouter Verhelst wrote:
>
> > share /usr between multiple systems today; but nobody does it, because
> > - Keeping your software on a central fileserver introduces a single
> > point of failure that you don't have if you don't do the central
> > fileserver thing
>
> That sounds like everyone who uses LTSP, which is pretty common in
> governments and business.
Actually, if you'd read my email slightly more carefully, you'd have
seen that I referred to the LTSP model of using a central *image* that
is netbooted in the next paragraph. I'm well aware that LTSP uses a
central server -- they commonly use NBD for that, and I maintain
nbd-server, so they're one of my major users.
I'm not saying that using a central server, and there by introducing a
single point of failure, is necessarily a bad idea. If it frees you of
the need to synchronize your servers, it is in fact a very good idea.
Alternatively, if you go through the effort of installing every system
locally and making sure that they are synchronized, then not having a
single point of failure is also a good idea.
What I was trying to point out was that this mode gives you a hybrid
situation combining the downsides of both the above modes and none of
the advantages. That's not very good.
Now if this were something that would not cost us very much to
implement, then that wouldn't matter all that much. But that's not the
case.
--
The volume of a pizza of thickness a and radius z can be described by
the following formula:
pi zz a